https://doi.org/10.1140/epja/i2012-12177-3
Regular Article - Theoretical Physics
A microscopic explanation of the isotonic multiplet at N = 90 and of the F-spin multiplet in Dy-Hf
Ramjas College, University of Delhi, 7, Delhi, India
* e-mail: jbgupta2011@gmail.com
Received:
19
April
2012
Revised:
25
September
2012
Accepted:
10
October
2012
Published online:
3
December
2012
The N = 90 isotones of Nd, Sm, Gd and Dy, with almost similar deformed level structure and associated with X (5) symmetry, form the isotonic multiplet in Z = 50–66, N = 82–104 quadrant. This is explained microscopically in terms of the Nilsson level diagram. Using the Dynamic Pairing-Plus-Quadrupole model of Kumar-Baranger, the quadrupole deformation and the occupancies of the neutrons and protons in these nuclei in the Nilsson orbits have been calculated, which support the formation of N = 88, 90 isotonic multiplets. The existence of the F-spin multiplets, with almost identical spectra, recognized in earlier works, in Z = 66–82, N = 82–104 quadrant, is also explained microscopically in our study.
© SIF, Springer-Verlag Berlin Heidelberg, 2012